It is a matter of common experience that shoe laces often come untied when a person is walking or conducting sport activities such as jogging, running, playing ball, skating or skiing. The tendency of a shoe lace to come untied can, of course, become dangerous because it can cause tripping or falling which may result in serious injury. As mentioned in U.S. Pat. No. 4,247,967, ordinary shoe laces loosen or come untied because they are usually formed of relatively smooth woven yarn material. The smooth surface of laces made of such yarns provide little gripping power at the points where the laces cross. Accordingly, said patent discloses a shoe lace made of a binding having "hook-type" (male) and "loop-type" (female) fastening material such as Velcro. The male and female Velcro fasteners are readily engaged by pressing the complementary fabric unit together and insures against loosening of the lace, or coming untied. In order to untie the shoe lace, the fastening means are disengaged by peeling the complementary portions apart from each other.
Others who have been concerned with the safety of joggers and runners who exercise at night, have suggested the use of shoe laces which have enhanced visibility. Thus, as disclosed in U.S. Pat. No. 4,651,447, shoe laces are provided which are formed of materials having at least one exposed retroreflective surface, and an adhesive surface.
Neither one of the aforementioned patents is concerned with braided shoe laces. However, U.S. Pat. No. 4,423,539 discusses several earlier patents relating to shoe laces including shoe laces made of woven or braided elastic strands. As further indicated in said patent, elastic laces have been commonly made in the past by braiding cotton or other textile yarn around an elastic rubber core. Even though such laces are elastic, "they are not at all durable or satisfactory for running shoes." In order to improve the durability and stretchability of the shoe laces, the aforementioned patent recommends employing a plurality of spacedly-arranged longitudinal elastic strands held together by cotton in a web configuration. So far as it is known, however, braided shoe laces of the type described or referred to in U.S. Pat. No. 4,423,539 are not entirely satisfactory because they lack one or more of the essential requirements which insures against the shoe lace coming untied, or they lack the requisite degree of durability.
It is therefore an object of the present invention to provide slip-resistant durable shoe laces which are particularly suitable for footwear used by joggers, runners and by persons participating in other sports activities.
It is another object of this invention to provide shoe laces which do not loosen or come untied during use.
It is also an object of this invention to provide shoe laces which, in addition to the foregoing characteristics, are safe and provide a retroreflective surface to enhance the visibility in the dark.
It is yet another object of this invention to provide shoe laces having the improved safe and attractive features heretofore described.
The foregoing and other advantages and features of this invention will be more readily comprehended from the ensuing detailed description and the accompanying drawings.